“Crickey, Dan!” groaned Billy. “We’ve lost it.”
“Oh, I guess the old stump hasn’t moved,” said Dan, cheerfully. “It’s up yonder—somewhere!”
At that moment they again caught sight of the rosy glow in the tree-tops. “See!” exclaimed Dan. “More heat. Jingo! that must be a great draft.”
“They must have some way of shutting off the draft, and then opening it again,” said Billy, in a puzzled tone. “There! it’s gone.”
“I’ve got it” exclaimed Dan, suddenly. “I bet that’s a forge.”
“A forge?” repeated Billy, in wonder.
“They’d want a tall chimney for a forge on account of needing a strong draft,” declared Dan. “That’s what it is.”
“But a forge in a cave?” queried his brother, doubtfully. “What for?”
“Ah! that’s another question,” returned Dan. “I don’t see that far, yet.”
But in secret Dan believed he had guessed the business of the men who had once, at least, occupied the cave, whether they were there now, or not. He said nothing to Billy about this, however.